Navigating change: A transitional year in ballast water management in Canada, 2020

Ballast water discharge has long been recognized as an important vector for introducing aquatic invasive species, prompting the implementation of ballast water management regulations globally to mitigate this risk.Recently, ballast water management regulations have transitioned to performance-based standards, with most vessels installing and operating onboard ballast water treatment systems.To evaluate the adoption and utilization of ballast water treatment systems during this transition period, this study analyzed ballast water reporting form data from vessels arriving in Canada from foreign ports in 2020.Between January and December, the percentage of vessels discharging ballast water with treatment systems installed increased from 38% to 62%, and the percentage of discharge volume managed using treatment systems doubled, increasing from 22% to 45%.However, not all vessels with treatment systems were using them, with monthly usage rates ranging from 63% to 78%.When treatment systems were not in use, ballast water was often managed through ballast water exchange, while some ballast was sourced from the mid-ocean or discharged unmanaged due to regulatory exemptions related to the ballast water exchange exemption zones.Possible factors preventing consistent use of ballast water treatment systems include equipment breakdown, maintenance issues, crew inexperience, or challenging port water conditions hindering system performance.These factors underscore the need for robust contingency measures until advancements in treatment system technology or reliability provide lasting solutions.